Fuel System for Carb 408 sbc

[Michael Bennett]

You could definitely run a TBI pump and regulate that down. A stock TBI pump should be making about 20psi give it take a pound or two.But you need a return style regulator

I'm thinking about trying the 89 Vette pump suggested earlier with this pickup. Just need to make sure it will flow enough to support the engine.

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[Michael Bennett]

Giving a call would be good idea. I looked at them this morning and other than the one screenshot I sent, all the others are 60 psi. This was true for the return and the non return style.

60 psi is the requirement for the sniper system, so could be why all the ones shown fit that requirement.

Called Holley and waited for 45 minutes to talk to them. They didn't come up with anything other than the ones we had both already found.

 

[78Delta88]

Called Holley and waited for 45 minutes to talk to them. They didn't come up with anything other than the ones we had both already found.

Attached screenshots. V6 sending units for 80 Malibu.

Either one would work. The one listed with vapor return has the 3 lines coming from it. The middle line looks about 1/4 inch and would be vapor return from canister. The other lines look to be 3/8 but hard to tell from just photo.

I would suggest the one with the three lines and remove the bell if using active return from regulator. But by using these you don't have to drill tank to add a return barb.

To add the pump you cut the line and add the pump, yet you will still need a support for the sending unit and a pass through wire for the pump.

 

[78Delta88]

Attached screen shot is from S10 TBI.

It has the setup for the pump.

If you want to go this route, I can tell you how to setup. Seems difficult but it really isn't. Just take good measurements and some finesse for the sender unit to keep your gas gauge accurate.

If you look at line layout, supply is 3/8 and return is 1/2. If that's not the case, then supply is 5/16 and return is 3/8. I don't have one in front of me. The best scenario is supply 3/8 and return of 1/2. The TBI pump is designed to run full on. The pressure regulator on the TBI unit is 9 psi and there is no rail, it's designed to run full on during engine operation.

On the power feed for the TBI is: ECU energized about 8 seconds prior to start and then when "key on engine on", power is live to the oil pressure switch. From the oil pressure switch is the electrical feed to the Pump.

Pump operation stops when key is turned to off. So you don't have to worry about pump failure, pump is not designed to "rest". When engine is on, it is on and stays full on. It is a bypass pump system, it is designed to not shut off until key turned to "off".

 

[Michael Bennett]

Attached screenshots. V6 sending units for 80 Malibu.

Either one would work. The one listed with vapor return has the 3 lines coming from it. The middle line looks about 1/4 inch and would be vapor return from canister. The other lines look to be 3/8 but hard to tell from just photo.

I would suggest the one with the three lines and remove the bell if using active return from regulator. But by using these you don't have to drill tank to add a return barb.

To add the pump you cut the line and add the pump, yet you will still need a support for the sending unit and a pass through wire for the pump.

That's crazy, mine was a v6 car originally and only has two outlets, no return. Maybe those are for California cars. Definitely will check out. If I go EFI though the Regal sending unit would probably be easier than modding the S10 unit.

 

[78Delta88]

That's crazy, mine was a v6 car originally and only has two outlets, no return. Maybe those are for California cars. Definitely will check out. If I go EFI though the Regal sending unit would probably be easier than modding the S10 unit.

Could be I was going to look up the Regal next. If the tanks are the same then that is your turn key fix.

It will definitely be less money, as the Holley setups are all around the $400.00 mark.

 

[78Delta88]

Just checked. Tanks are the same: GM3A, 17 gallon.

Screenshots attached.

 

[78Delta88]

Attached screenshots show the sending unit you need.

So basically just install the new setup with a TBI pump. Setup your regulator with a 6 psi bypass return.

On the OPS (oil pressure switch) you then just need to know if you need 1/8 NPT or 1/4 NPT. The switch closes at about 5 psi.

 

[Michael Bennett]

Attached screenshots show the sending unit you need.

So basically just install the new setup with a TBI pump. Setup your regulator with a 6 psi bypass return.

On the OPS (oil pressure switch) you then just need to know if you need 1/8 NPT or 1/4 NPT. The switch closes at about 5 psi.

I found that sending unit before. Is there a specific oil pressure switch?

 

[78Delta88]

I found that sending unit before. Is there a specific oil pressure switch?

Yes I can send part numbers